Thanks to all of you for your comments.
Here's a little more background on the bug and the image. When I found her in a field near my house, she was in the process of mating with a bright green male half her size. By the time I could get my photo gear and set it up, she was eating him. That was a shame, but common among mantids; the male contributes its body as nutrients for the next generation.
The reason everything is in focus is that I was able to use focus bracketing and stacking. This is normally quite hard (or impossible) with live, active bugs, so up until recently I have rarely employed it. But several things contributed to success in this instance. Most importantly, my Olympus E-M1 received a firmware update some months ago that provides in-camera focus bracketing, as well as limited in-camera stacking. It can shoot a small-medium bracket set very quickly, requiring no intervention (i.e., shifting the camera or manual focus adjustments) by the user. It thus becomes a bit more practical (though still quite tricky) to use bracketing with macro shots of active subjects, if they will at least occasionally hold still for a moment or two. Mantids are more cooperative than most bugs in that regard.
And I was also very lucky here. The bug may look like she is smiling, but I'm pretty sure the thoughts going through her head were more menacing. What you see here is her "threat posture", raising up and fanning her wings out to look larger while adopting a ready-to-fight stance. I'm not sure whether it was my movement, the camera, or her own reflection in the lens that provoked it, but she held it without moving just long enough for me to fire off a 10-shot bracket at f/5.6.